The Doctor is summoned to a hospital on New Earth in the far future. The
facility is run by the cat-like Sisters of Plenitude, and the Doctor is
astonished to find that the Sisters' medical technology is centuries ahead
of its time. Meanwhile, Rose is lured into a trap by Cassandra, the last
human, who aims to restore her long-lost beauty while uncovering the
secrets of the Sisters of Plenitude.

Production

One of the early successes of Doctor Who's first season back on
the air was The End Of The World.
Considerable word of mouth was excited by its vastly far-future setting
and plethora of alien creatures, and in particular its
digitally-rendered villainess, Cassandra. For the programme's next
season, executive producer Russell T Davies was eager to write a sequel
-- not just in the hope of catching lightning in a bottle twice, but
also to further reinforce (as with the appearance of Harriet Jones in The Christmas Invasion) that the change in
lead actor from Christopher Eccleston to David Tennant had not
fundamentally altered the show.

Davies therefore came up with an idea originally called “Body
Swap”. In addition to Cassandra and the Year Five Billion setting,
Davies also decided to bring back another character from The End Of The World: the monolithic Face
of Boe. Davies had devised a “secret” which the Face of Boe
(who, it had been implied in the first season's The Long Game, was incredibly long-lived)
would impart to the Doctor. Originally, this secret would be divulged at
the end of “Body Swap”, but when Doctor Who's renewal
was extended to include a third year in June 2005, Davies opted to
postpone its revelation.

In the original climax, the Doctor was forced to let the
Intensive Care patients die

“Body Swap” was initially set on a planet named Coffra, but
this had changed by the time the adventure gained its final title of
New Earth. The Sisters of Patience became the Sisters of
Plenitude, and the medical facility was at one point called the Hospital
of Evergreen Days. Cassandra's servant was envisioned as a dwarf named
Zaggit, but as the character's importance grew during the scripting
process, he developed into Chip. The climax of the story changed
significantly from Davies' original conception; at first, the Doctor
would have been forced to let the Intensive Care patients die, but
Davies came up with a more optimistic solution when Steven Moffat (who
had written The Empty Child / The Doctor
Dances for the 2005 season) observed that Davies had a penchant
for creating interesting characters and then doing away with them.

As for Cassandra herself, Davies intentionally kept her appearances as a
“stretched skin” to a minimum, because these scenes were
gruelling to computer-animate. Instead, Davies came up with Cassandra's
ability to take over the bodies of others, which also fulfilled a
promise to Billie Piper that she would be given a comic role in the new
season, as a counterpoint to the often very serious material she had
tackled the year before.

New Earth formed part of the first production block for the new
Doctor Who programme's second season, directed by James Hawes
alongside The Christmas Invasion and School Reunion. The first sequences filmed
for New Earth were all those featuring Zoe Wanamaker in person;
Wanamaker had thoroughly enjoyed recording Cassandra's lines for The End Of The World and was happy to take
an on-camera role in the sequel, but also had very limited availability.
Cassandra's party was actually held on August 1st at the Bar Orient
restaurant on Cardiff Bay. The same day, the departure of the TARDIS
from London was recorded elsewhere in Cardiff, at Loudoun Square in
Gabalfa.

Production did not resume until August 22nd, when special effects work
was conducted at HTV Studios in Culverhouse Cross, Cardiff. Things then
picked up in earnest in September. By this time, most of The Christmas Invasion and School Reunion had been completed and the
recording block as a whole had fallen badly behind schedule. As a
result, several scenes were dropped from Hawes' plans. Many of these
concerned the Duke of Manhattan and Frau Clovis. Originally, they first
appeared in the hospital foyer when the Doctor initially arrives; as
scripted, the Doctor immediately earns the Sisters of Plenitude's
disfavour when he saves the Duke's life. Later, Clovis mutinies when the
Duke refuses to help defend the hospital against the Intensive Care
patients.

Work was interrupted to repair the Face of Boe, which was
damaged by Billie Piper's boyfriend

Material in the hospital foyer was performed on September 5th, at the
Millennium Centre in Cardiff. The only work carried out on New
Earth over the next two days involved smoke effects at the BBC Model
Unit in London. Recording proper continued on the 9th and 10th, when the
disused Ely paper mill in Cardiff -- the same one which had featured as
the Nestene lair in Rose the year before
-- played host to scenes in the Intensive Care Unit. Cast and crew then
repaired to the main Doctor Who studio space, Unit Q2 in Newport,
for a week. From September 12th to 16th, scenes in the hospital wards
and shafts were taped, as was material in the TARDIS. At one point, work
had to be interrupted so that repairs could be made to the Face of Boe
prop, which had been inadvertently damaged by Piper's boyfriend.

Location filming resumed on September 19th at Tredegar House in Newport,
where material in Cassandra's lair was recorded. This continued on the
21st and 22nd. The final exterior scenes to be recorded were those
outside the TARDIS on New Earth. The locale used was actually Worm's
Head on the Gower Peninsula near Swansea, on September 26th.
Unfortunately, the shoot was hampered by high winds and rain, forcing
the abandonment of the final scene to be recorded. Planned to bridge the
final hospital sequence and the material at the party, this would have
seen the Doctor reminding Cassandra (now in Chip's dying body) that he
still hasn't forgiven her for the deaths she caused in The End Of The World. The uncooperative
weather was not the only misfortune to befall the day's recording: it
was belatedly discovered that a camera had malfunctioned during the
shoot, resulting in the loss of several close-ups.

Two more days at Unit Q2 were needed on October 7th and 8th; these
chiefly dealt with scenes in the hospital lift and in the lift shaft.
The final material taped for New Earth was also studiobound; a
pick-up shot of the Doctor emerging from the TARDIS at Cassandra's party
was recorded on November 3rd.

Davies had always been uncertain of the placement of New Earth in
the season schedule. Before production began, he suggested it might swap
places with The Girl In The Fireplace
(which was intended to be the second story at that stage). Closer to
transmission, there was discussion of running Tooth And Claw first and New Earth
second, inspired at least in part by the latter's fraught production. In
the end, however, it was felt that such a move would necessitate too
many changes to New Earth's narrative, and so the adventure was
kept in the pole position.

There was discussion about swapping New Earth and Tooth And
Claw in the running order

Not long before its broadcast, producer Phil Collinson requested changes
to some of the computer-generated effects shots of the hospital
exterior. Previously, the facility had been depicted as being removed
from any other buildings, but Collinson thought this looked unnatural.
Additional structures and architectural detail were hastily added to the
images in response to these criticisms.

As with all the other second-season episode, New Earth was
trailed by a one-minute prologue which could be downloaded from the BBC
Doctor Who website or via a mobile phone. These teasers -- all of
which were written by Gareth Roberts, who had also penned the Attack
Of The Graske interactive game which had appeared on the BBC's
digital service at Christmas -- initially went under the banner
“Vortext” (after names such as “Whosode”,
“Epi-mobe” and “Who Alert” were rejected) but
were rechristened TARDISodes at a late stage.

The 46-second TARDISode for New Earth took the form of an
advertisement for the hospital and featured Anna Hope reprising her role
as Novice Hame. It was recorded on January 26th, 2006 at Enfys
Television Studios in Cardiff. The TARDISode became available on
March 31st. Two weeks later, Doctor Who repeated the pattern of
the 2005 season by debuting on Easter Saturday, April 15th.